Circulatory System Functions Quiz

A circuit where electrons can follow multiple paths, allowing for simultaneous flow to different components.

The delivery of oxygen and nutrients to cells and the removal of carbon dioxide and waste products.

Transporting nutrients, like glucose and amino acids, from the digestive system to cells for energy and growth.

White blood cells are transported throughout the body to fight infections and pathogens.

Removing metabolic wastes, such as urea and lactic acid, from cells and transporting them to excretory organs.

Cardiac valves are structures within the heart that control the flow of blood between chambers and prevent backflow.

Cardiac muscle cells have specialized properties, including the ability to contract rhythmically and spontaneously, and to communicate with each other through electrical signals.

Cardiac muscle cells communicate with each other through gap junctions, which allow electrical signals to pass directly between cells, ensuring synchronized contractions.

Located between the atria and ventricles, these valves open when atrial pressure exceeds ventricular pressure, allowing blood flow into the ventricles.

These valves ensure blood flows in one direction from the atria to the ventricles by opening when atrial pressure is higher and closing when ventricular pressure is higher.

These cord-like tendons attach the AV valves to the papillary muscles, preventing them from inverting (turning inside out).

Muscles located in the ventricles of the heart that are connected to the AV valves by chordae tendineae.

Also known as the tricuspid valve, it has three cusps or leaflets and is located on the right side of the heart.

Also known as the mitral valve, it has two leaflets and is located on the left side of the heart.

Located between the ventricles and the arteries leaving them (pulmonary artery and aorta), these valves prevent backflow of blood into the ventricles.

These valves are positioned between the right ventricle and the pulmonary artery, allowing blood to flow into the lungs.

Specialized cardiac muscle cells that can generate their own action potentials, causing the heart to beat rhythmically.

The sympathetic nervous system (SNS) is triggered by stimuli like fear or physical stress, leading to the release of epinephrine. This hormone increases heart rate.

Increased blood flow to peripheral tissues, often caused by illness or injury, also stimulates the SNS, resulting in a higher heart rate.

These cells have unique ion channels that cause their membrane potential to depolarize slowly until an action potential is triggered.

A specific type of ion channel found in autorhythmic cells that allows both sodium (Na+) and potassium (K+) ions to enter the cell, causing a depolarization of the membrane potential.

The sinoatrial (SA) node, located in the right atrium, is a cluster of autorhythmic cells that initiate the heart's electrical impulses.

The upstroke of the action potential in autorhythmic cells is caused by the opening of L-type calcium (Ca2+) channels, rather than sodium (Na+) channels as seen in other cells.

The heart's electrical conduction system is a network of specialized autorhythmic cells that transmit electrical impulses, coordinating the contraction of the heart chambers.

A condition where the heart's electrical activity is disrupted causing the ventricles to beat independently of the atria, resulting in two rhythms on an ECG.

The volume of blood pumped by one ventricle in one minute.

The period during the cardiac cycle when the heart muscle is contracting.

The period during the cardiac cycle when the heart muscle is relaxing.

The process of the heart muscle contracting while the valves are closed, increasing pressure but not volume.

The period of relaxation where all heart valves are closed, and no blood flows in or out.

Sounds produced by the heart due to the closure of valves during the cardiac cycle.

The mechanical activity caused by the electrical activity of the heart, including contraction and relaxation.

The AV node delays the signal from the atria to the ventricles, allowing the atria to contract and fill the ventricles with blood before the ventricles contract.

The bundle of His and Purkinje fibers are specialized pathways in the heart that quickly transmit electrical signals from the AV node to the ventricles, ensuring synchronized contraction of the ventricles.

The wave of excitation spreads from the AV node, travels through the bundle of His, and then branches into the right and left bundle branches. These branches further extend into the Purkinje fibers, which rapidly distribute the signal to the ventricular muscle.

Gap junctions between cardiac muscle cells allow for direct electrical communication, ensuring that the contraction wave spreads evenly throughout the ventricles and that all muscle cells contract simultaneously.

The coordinated activity of the SA node, AV node, bundle of His, and Purkinje fibers ensures that the heart beats in a regular and efficient way, pumping blood throughout the body.

The SA node, located in the right atrium, acts as the pacemaker of the heart, generating electrical signals that initiate the heartbeat.

The interatrial pathway and the internodal pathways spread electrical signals from the SA node to the rest of the atria and the AV node.

The AV node is located in the junction between the atria and ventricles. It delays the signal from the atria, allowing atrial contraction and efficient filling of the ventricles before ventricular contraction.

The volume of blood that a ventricle pumps out in one minute. It is the same for both the left and right sides of the heart.

The number of times the heart beats per minute.

The amount of blood ejected from the left ventricle with each heartbeat.

The specialized tissue in the right atrium that initiates the heartbeat. It acts as the heart's natural pacemaker.

The branch of the autonomic nervous system that slows down heart rate.

The branch of the autonomic nervous system that speeds up heart rate.

The nerve that transmits parasympathetic signals to the heart, slowing heart rate.

The nerve that transmits sympathetic signals to the heart, increasing heart rate.